fix: 🤔 remove placeholder for fixed column sample

[coraliefeil]

Current behavior

https://solid-design-system.fe.union-investment.de/x.x.x/storybook/?path=/story/styles-sd-table-cell--samples
On this page we have a placeholder for "Simple Table, First Column Fixed"

This can be deleted because we show this sample in the advanced samples here
https://solid-design-system.fe.union-investment.de/x.x.x/storybook/?path=/story/styles-sd-table-cell--advanced-samples as "Fixed, vertical, left header with shadow table"

Expected behavior

Steps to reproduce

Technical Information

DoR

• Item has business value
• Item has been estimated by the team
• Item is clear and well-defined
• Item dependencies have been identified

DoD

• Documentation has been created/updated (if applicable)
• Migration Guide has been created/updated (if applicable)
• Relevant E2E tests (Features, A11y, Bug fixes) are created/updated
• Relevant stories (Features, A11y) are created/updated
• Implementation works successfully on feature branch

[yoezlem]

PR: https://github.com/solid-design-system/solid/pull/1045/files